[rsavage]

Brian,
If the clutch is engaging when the A/C is turned on isn't it working as it should? With the belt off and engine off obviously, does the pulley on the compressor turn freely without turning the compressor? ( just grip the pulley not the front of the clutch). If so you might have a low oil problem in the system or a compressor that is going bad. You could put a vacuum on the system and draw in 4 or 5 ounces of R12 compatable oil (ester I believe) and see if that helps. The compressor will actually make some noise when low on oil, is yours? These old compressors use a lot of power to turn. Once the belt starts slipping it usually means you have to get another as I never had much luck getting them to grip good again. They need to be real tight too which is no easy feat on these compressors and brackets. Good luck,.